System for increasing the aerodynamic and hydrodynamic efficiency of a vehicle in motion

ABSTRACT

The system includes radiation generation and transmission components which radiate tuned microwave electromagnetic energy outwardly from a vehicle through an antenna into a fluid medium through which the vehicle is moving. The microwave radiation is at the frequency of harmonic resonance electromagnetic excitation of the molecules of the medium which produces efficient heating of the fluid resulting in a reduction of the mass density thereof. This reduction decreases the drag forces acting on the vehicle resulting in a greatly enhanced aerodynamic and/or hydrodynamic efficiency and also decreases the intensity of the shock waves (which often lead to sonic booms). An aircraft&#39;s dramatically higher speed in the surrounding rarefied medium can make it appear to be travelling at &#34;supersonic&#34; speeds.

BACKGROUND OF THE INVENTION

The invention relates generally to systems for facilitating the motionof a vehicle through a fluid medium and, more particularly, to systemsfor facilitating the motion of aircraft through the atmosphere in orderto significantly reduce the amount of energy required to propel theaircraft, significantly increase the maximum speed of the aircraft andsubstantially reduce the intensity and incidence of shock wavesassociated with the motion.

The well known sonic boom is a significant problem presented by aircraftcapable of flying at supersonic speeds. The sonic boom is so annoyingand so often damaging to homes, buildings and other property thatmilitary aircraft have been required to attain supersonic speeds overlarge bodies of water or sparsely populated areas in order to minimizethese undesired effects. With the increasing prevalence and viability ofcommercial supersonic flight resulting from government research anddevelopment efforts and the increasing viability of commercial aircraftdesigned for speeds well in excess of supersonic speeds, the sonic boomeffects have become more problematic.

The sonic waves generated by supersonic flight are also detrimental tothe practicality of such supersonic flight because they result in anaerodynamic drag effect which retards the velocity of the aircraftthereby requiring more energy to propel it. For this reason and becausefrictional forces resisting movement of an aircraft increase with thesquare of the aircraft's velocity, high velocity aircraft as well asother types of high velocity vehicles typically require higher fuelexpenditures and concomitantly produce higher levels of pollution aswell as high consumption of fuel often made from nonrenewable naturalresources. This high pollution and high fuel consumption is a seriouseconomic and environmental problem that has been addressed by designingengines that have higher fuel efficiencies and lower pollutantemissions. These design efforts have successfully produced engines thatare very efficient. Unfortunately, the proliferation of motorizedvehicles of many sorts has nevertheless resulted in an increase inglobal pollution and higher energy consumption. In addition, thepollution reduction and energy efficiency augmentation systems forconventional engines have become so effective that further improvementson systems used on conventional engines is not likely to producesubstantial improvements. Consequently, many engineers have sought toreduce pollution and increase energy efficiency of conventional vehiclesby seeking to make modifications in other areas.

Ships and submarines are notoriously slow moving. Increases in thespeeds of surface ships are prohibitively expensive, and this is thereason most commercial shipping operates at around twenty knots.Submarines, lacking the bow wave common to surface ships can travelfaster, but substantial power sources are needed for a modest advantageover the speeds of surface ships. What's worse, there is tremendousacoustical vibration associated with these high speeds, which causes thesubmarine to lose its stealthy advantage normally afforded by theocean's depths. Torpedoes can move faster than submarines, but againthere are tremendous consumptions of the limited non-nuclear fuelsavailable along with the accompanying warning from its acousticalsignature that the weapon has been fired.

Many have sought solutions to the aerodynamic applications of theseproblems by developing systems which reduce the mass density of themedium through which a vehicle is moving and thereby reduce the dragforces acting on the vehicle while it is in motion. Some of thesesystems have specifically sought to reduce the mass density of theatmosphere through which aircraft are traveling and thereby reduceaerodynamic drag acting on the aircraft. This desired goal would notonly provide increased fuel efficiency but also enable the aircraft toachieve higher maximum attainable speeds. As an additional benefit, theintensity and incidence of shock waves associated with the aircraftwould be reduced resulting in elimination of or reduction of theintensity of a sonic boom otherwise produced when the aircraft attainssupersonic speeds.

Some prior art methods and devices for reducing the mass density of theatmosphere through which an aircraft is flying have utilized incendiarycompounds to heat the air and thereby reduce the mass density thereof.Two examples of such methods are disclosed in U.S. Pat. Nos. 4,917,335to Tidman and 3,620,484 to Schoppe. The Tidman method essentiallygenerates and maintains combustion of a flammable compound which isejected from the aircraft directly into the atmosphere immediately infront of the aircraft. The Schoppe method utilizes a mechanical flamethrower to also produce combustion directly in front of the aircraft butadditionally uses a blunt nosed body to compress the air prior to thecombustion for enhanced efficiency thereof. Thus, in both these methods,the aircraft consequently travels through a fireball of reduced massdensity which reduces aerodynamic drag and the incidence and severity ofsonic boom. However, a primary disadvantage of such a method is that thechemical reaction as well as the ejection of the combustible mass maynot be fast enough to rarefy the atmosphere in front of an aircrafttraveling at supersonic speeds. In addition, the required speed ofcombustion may result in generally incomplete combustion and therebywasting of fuel and production of inordinate amounts of pollutants. Therequirement of a blunt body precludes the system from being used toreduce the density of the atmosphere in front of the entire aircraft or,more specifically, in front of wing leading edges as well as otherportions thereof.

Other prior art systems designed to reduce aerodynamic drag and sonicwaves rarefy the atmosphere in front of the aircraft by moving airmolecules rearwardly from the leading edges of the aircraft. An exampleof such a system is disclosed in U.S. Pat. No. 3,446,464 to Donald. TheDonald apparatus utilizes electrodes placed both at the leading edgesand rearward of the leading edges. Different electrical potentialsapplied to the electrodes produce an electrical field which moves theair molecules rearwardly from the leading edges thereby reducing thebuildup of air pressure in front of the leading edges. However, aprimary shortcoming of the Donald apparatus is that it does not directlymove air molecules which are in front of the leading edges and thus isof limited effectiveness in reducing aerodynamic drag and sonic boom.

Since the 1940's some designers of aircraft have sought to reduceaerodynamic drag by radioactive excitation of the air molecules proximalto or adjacent to the aircraft. Early designs have utilized radioactivecoatings on the skins of the aircraft to ionize the air molecules at theboundary layer at the aircraft fluid-solid interface thereby inducingrepelling or attractive forces on these ions and/or to induce avibrational or rotational excited state in the air molecules therebyaltering their viscosity. A technologically improved design utilizingsuch a concept is disclosed in U.S. Pat. No. 3,510,094 to Clark in whichthe magnitude and number of alpha and beta particle emissions from theradioactive layer on the aircraft skin is controlled. However, a primarydisadvantage of these types of designs is that they do not have a highdegree of energy efficiency in reducing the density of the air in frontof the aircraft where it is most needed because the emissions radiateoutwardly in all directions. Moreover, the radioactive emissions caninterfere with aircraft computer, radio and radar systems as well asbeing potentially dangerous to personnel within the aircraft or in thevicinity of the aircraft.

Still other prior art systems utilize laser beam radiation to heat theair passing through the beam and thereby rarify the air through whichthe aircraft is moving. An example of such a system is disclosed in U.S.Pat. No. 5,263,661 to Riley. The Riley device uses a laser radiating abeam along the leading edge of an aircraft wing to the tip. The airpassing through the beam as the aircraft flies through the atmosphere isheated and rarified thereby compressing more slowly as a result of theaircraft's motion than it normally would and creating a lower massdensity thereof which is less favorable to development of a sonic boom.However, a primary disadvantage of such a system is that it has a highpower requirement because laser radiation does not efficiently produce ahigh degree of heat energy in the air molecules.

Consequently, what is needed is a system for reducing the mass densityof the air in the path of flight of the aircraft as well as adjacent toaircraft skin surfaces in order to maximize reduction of the forces offriction and other drag forces acting on the aircraft during flight.What is also needed is a system for reducing the mass density of the airproximal the aircraft which is able to provide such reduction of massdensity very quickly and with a relatively high degree of energyefficiency.

SUMMARY OF THE INVENTION

It is a principal object of the present invention to provide a systemfor reducing the mass density of the fluid medium in front of a vehiclemoving through the medium in order to reduce drag forces and sonic wavesproduced by the motion.

It is also an object of the present invention to provide a system forreducing the mass density of the fluid medium adjacent to and proximalto lateral and rearward portions of a vehicle moving through a fluidmedium in order to reduce drag forces and sonic waves produced by themotion.

It is also an object of the present invention to provide a system forreducing the mass density of the fluid medium through which a vehicle ismoving which achieves the mass density reduction quickly andeffectively.

It is also an object of the present invention to provide a system forreducing the mass density of the fluid medium through which a vehicle ismoving which is relatively safe.

It is also an object of the present invention to provide a system forreducing the mass density of the fluid medium through which a vehicle ismoving which is energy efficient.

It is also an object of the present invention to provide a system forreducing the mass density of the fluid medium through which a vehicle ismoving which entails minimal interference with vehicle electroniccomponents.

It is also another an object of the present invention to provide asystem for reducing the mass density of the fluid medium through which avehicle is moving which is effective at both subsonic and supersonicspeeds.

It is an object of the present invention to provide a system forreducing the mass density of the fluid medium through which a vehicle ismoving which provides heat energy transfer with vehicle engine systemsfor enhanced energy and power efficiency.

It is an object of the present invention to provide a system forreducing the mass density of the fluid medium through which a vehicle ismoving which provides a high degree of efficiency in producing a highdegree of mass density reduction of the fluid medium.

Basically, the aerodynamic and hydrodynamic efficiency augmentationsystem of the present invention achieves its goal of reducing the massdensity of the fluid medium through which a vehicle is moving by heatingthe fluid medium proximal to the vehicle to a high temperature. Theheating is accomplished via radiation of tuned electromagnetic poweroutwardly from the vehicle into the fluid medium. The electromagneticradiation is within the microwave range in order to maximize transfer ofelectromagnetic energy received by the fluid medium molecules into heatenergy. In addition, the frequency of the electromagnetic radiation isat the harmonic resonance frequency of electromagnetic excitation of theparticular type of molecules of which the medium is composed. Radiationat the harmonic resonance frequency maximizes the power transferefficiency of the heating of the fluid medium provided by the system ofthe invention.

The system of the present invention is particularly well suited for bothsubsonic and supersonic aircraft for which the effects of aerodynamicdrag and sonic wave production are more pronounced. The system of theinvention is also very suitable for Force Projection Vehicles typeaircraft which utilize wing-in-ground effect airfoils generating almostdouble the normal lift capability because of a combination of groundeffect and downwardly projecting airfoils (at the wing tips) thatconfine inrushing air. Force Projection Vehicles normally cruise twentyfeet above the sea over which it is most efficient but can also flyabove land although at a higher altitude. Their low altitude capabilityrenders them very advantageous in military operations because of theirrelative invisibility to radar. However, Force Projection Vehicles,although also advantageous because effective and efficient in transportof large and heavy cargo, are currently limited to flight at relativelyslow speeds. By substantially increasing maximum speed capability, theaerodynamic efficiency augmentation system can overcome this importantshortcoming of Force Projection Vehicles. In addition, the system of theinvention is also well suited for transatmospheric vehicles of manytypes. For these and similar types of applications in which the vehicleis moving through the atmosphere, the frequency of the electromagneticradiation is preferably at the harmonic resonance frequency ofelectromagnetic excitation i.e., electromagnetic absorption peak, ofoxygen. Oxygen (as well as water) has a substantial electric andmagnetic dipole which can easily be excited by tuned microwaveradiation. When heated, the oxygen molecules quickly transfer their heatenergy to adjacent nitrogen and other component molecules of the mediumresulting in quick and thorough heating of that portion of theatmosphere in the immediate path of the aircraft enabling the aircraftto fly in a thinner atmosphere resulting in reduced aerodynamic drag.Heating of the air decreases the pressure gradient at the front (andpreferably also the rear) of the aircraft thereby destroying thecoherency of the pressure fronts so that they do not add togethercoherently. This reduces the pressure gradients acting on the boundarylayer between the ambient air and the aircraft because they aredistributed over a larger region i.e., several meters rather thanseveral centimeters. The system of the invention essentially produces a"hot air bubble" around the aircraft which reduces the expended power attrue supersonic speeds because the coherent addition of pressure wavesaround the aircraft is degraded. This reduces or eliminates the energytransmitted to the shock cone i.e., the pressure field produced atsupersonic speeds and located at the rear of the aircraft and extendingtherefrom in a widening cone, thereby preventing or reducing the buildup of sonic waves and thus the reduction or elimination of a "sonicboom".

The system of the present invention can reduce the mass density of afluid medium comprising either a liquid or gas and may even be utilizedto reduce the mass density of a medium such as ice and thus increase thedynamic i.e., generally aerodynamic as well as hydrodynamic, efficiencyof a vehicle moving through either air or water. Thus, the system mayalso be utilized for waterborne and underwater vehicles. For these typesof vehicles the mass density of the water is reduced by irradiation atpreferably the harmonic resonance frequency of electromagneticexcitation of water. As with aircraft, this enables the waterborne andunderwater vehicles to move through the water with less inertial and/orviscous drag resisting their movement thereby allowing higher maximumspeed and acceleration and reduced fuel consumption.

The torpedo seems to be the easiest application platform to which toapply this phenomena. It could speed toward its target through anatmosphere of steam, stabilizing itself by a pair of fore and aft finshydroplaning through the surrounding water. A submarine could enjoy thesame advantage for a short period of time, unless some of the onrushingwater were piped aboard for cooling purposes. Surface ships, of thesizeable displacement of current ocean going naval and commercial marinevariety could ride a bubble of steam, effectively hydro-planing over theocean's surface. The "steam bubble" would be the vehicle which wouldtransmit the multi thousand tons of weight to the ocean's surface,replacing the conventional displacement of water which provides thebuoyant force for these vessels.

For transatmospheric (reentry) vehicle applications, the rarefaction ofthe atmosphere in the path of the vehicle also results in reducedfrictional heating of the nose cone or other portions of the vehicleprone to overheating and provides increased protection to internalcomputer, electronic or other components sensitive to heat which mayotherwise be damaged by or malfunction due to such heat generation.

For aircraft applications, the dynamic efficiency augmentation systemincorporates microwave radiation generators mounted in the engines ofthe aircraft. The microwave generators exchange heat with the airflowentering and exiting the engine resulting in improved energy efficiencyof both the engines and the generators. The induction airflow providescooling for the generators while the exhaust airflow is provided withincreased heating and thereby increased expansion of the engine exhaustgases resulting in improved thrust.

The output of the microwave generator is fed to an antenna whichtransmits the radiation through the interior of the aircraft andoutwardly therefrom into the atmosphere in order to heat and therebyrarefy the air in the path of the aircraft as well as preferablyrearwardly thereof. Thus, the microwave energy is radiated outwardlyfrom preferably both the leading and trailing edges of the aircraft. Inaddition to transmission directly into the air, radiation transmissionover portions of the skin of the aircraft produces heating andrarefaction of the air adjacent lateral surfaces of the aircraft whichtends to cling to the aircraft skin and produce viscous drag. The neteffect is the production of a hot bubble of rarefied air surrounding theaircraft while it is moving through the atmosphere reducing aerodynamicdrag on the aircraft and sonic wave generation (which also adds toaerodynamic drag). As a result, this reduces the fuel expenditurerequired for the aircraft to reach a desired speed and its maximumattainable speed is also increased. In addition, it may attainsupersonic speeds without generation of a sonic boom or with generationof a sonic boom of reduced intensity.

The calculations that follow provide a determination of the power neededas well as other parameters of the system components required to providethat power needed to heat the onrushing air from approximately zerodegrees to 1800 degrees Centigrade for a typical fighter aircraft inflight where the wings of the aircraft are D meters wide and theaircraft velocity is v=1000 mph. In the calculations it is assumed thatthe column of onrushing air is +/-y meters on either side of the wings.The mass of the air encountered by the wings (whose cold air density is1.29 kgrams/meter³) which must be heated every second is:

    2y×D×v×1.29×273 degrees Kelvin/2073 degrees Kelvin.

For a fighter aircraft with wings 12 meters wide, the power needed toheat the air +/-one meter above and below the wing's edge is:

    2×1×12×514×1.29×0.1317=2096 kgram/seconds.

The change in the specific heat of the air when its temperature isincreased from 100 degrees Centigrade (0.2404 cal/gram) to 1800 degreesCentigrade (0.2850 cal/gram) is 0.0446 cal/gram, and this leads to thefollowing:

    4.18 joules/cal.×0.0466 cal/gram=0.1864 Joules/gram=0.1864 kjoules/kgram.

Thus, the power which must be transmitted into the air in front of thewings is:

    0.1864 kjoules/kgram×2096 kgram/sec=391 kjoules/sec=0.4 megawatt.

To heat a column of air R meters in radius i.e., a size sufficient topermit the aircraft's fuselage and engine nacelles to pass therethrough,requires:

    π×R.sup.2 ×v×1.29 (density of cold air)×273 degrees Kelvin/2073 degrees Kelvin.

For an aircraft fuselage (and nacelles) 2 meters in radius requires:

    π×4×514×1.29×0.1317=1098 kgram/sec.

Thus, the power which must be transmitted into the air is:

    0.1864 kjoules/kgram×1098 kgram/sec=205 kjoules/sec=0.2 megawatt.

The total power required=0.4 megawatt+0.2 megawatt =0.6 megawatt.

Assuming that the air is heated by first ionizing the oxygen moleculesto their first ionization state, then this energy is shared by mutualexcitation (rotation) of the nitrogen molecules so that the nearby airmolecules eventually rise to an average temperature of about 1800degrees Centigrade. A triangular (in cross-section) beam +/-A° wide atthe front edge or tip portion of the aircraft fuselage (and enginenacelle) and extending b meters from it must be formed to heat thiscolumn of air. It will be assumed that all the oxygen molecules in thisregion will be ionized every time the 60 GHz beam produced by themicrowave generator fires, and the duty cycle of this transmission is0.0012. The first ionization potential, I_(p) is 4.8844×10⁴kjoule/kgram. It is believed that air exists in an ionized state out toat least b (6 meters). The instantaneous mass of oxygen excited by the60 GHz radio frequency beam=1 and is provided by:

    I=π×D×1/2b×(2×b tan A)×0.2 (air: 20% oxygen) ×1.29 kgram/m.sup.3 (cold air density)

    I=3.1416×30×6 m (assumed extent of ionization)×6×tan 1.24°×0.2×1.29

    I=18.9519 kgram.

The average ionization power expended P_(i) is:

    P.sub.i =I.sub.p ×I×transmission duty cycle=4.8844×10.sup.4 kjoule/kgram×18.95 kgram×0.0012.

Thus, the ionization power expended is:

    P.sub.i =1.1 megajoules per second=approximately 1 megawatt.

The half beam-width required to ionize a column of air meters (1 meter)in radius a distance b meters (6 meters) in front of the aircraft'sfuselage is given by:

    A°=tan.sup.-1 (r/b)=tan.sup.-1 (1/6)\19°/2.

The microwave beam is preferably radiated outwardly from the aircraftinto the column of air by means of a forward refocusing cassagrainantenna. The size z of the aperture which is the focus of the secondaryantenna of the forward refocusing cassagrain antenna (assuming 60 GHzpower) to generate a beam 2×A° wide is:

    z=65°×0.5 cm. (wavelength for 60 GHz RF)/(2×A°)=65°×0.5 cm./(19°)

    z=1.7 cm.

The size d of the cassagrain primary needed to form a beam 2.5° wide is:

    d=65°×0.5 cm./(A°)=65°×0.5 cm./(2.5°)=13 cm.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graphical representation showing the atmospheric attenuationof microwave radiation by oxygen and water molecules thereof andillustrating their absorption peaks.

FIG. 2 is a plan view of a typical turbofan jet engine suitable for usewith the aerodynamic efficiency augmentation system of the presentinvention.

FIG. 3 is a plan view of a continuous wave gyrotron type of microwaveradiation generator component of the aerodynamic efficiency system ofthe invention.

FIG. 4 is a plan view of the gyrotron mounted in an aircraft jet engineand positioned for heat exchange therebetween and also showing theantenna therefor.

FIG. 5A is a top plan view of the aerodynamic efficiency augmentationsystem of the invention mounted in an aircraft and showing the microwavebeams radiated into the atmosphere in front of the aircraft.

FIG. 5B is a side plan view of the aerodynamic efficiency augmentationsystem of the invention mounted in an aircraft and showing the microwavebeams radiated into the atmosphere in front of the aircraft.

FIG. 6 is a diagram of components of a first embodiment of the inventionshowing microwave beams radiated through a wing and fuselage portion ofthe an aircraft and radiated into the atmosphere in front of the leadingedge of the wing and into the rear of the trailing edge of the wing.

FIG. 7 is a diagram of the components of the first embodiment of theinvention shown in FIG. 6 for the radiation beams directed into theatmosphere in front of the leading edge of the wing and illustrating thebeam, the mirrors and antenna and the orientation and placement thereof.

FIG. 8 is a diagram of the components of the first embodiment of theinvention shown in FIG. 6 for the radiation beams directed into theatmosphere rearward of the trailing edge of the wing and illustratingthe beam, the mirrors and antenna and the orientation and placementthereof.

FIG. 9 is a diagram of the components of the first embodiment of theinvention shown in FIGS. 6, 7 and 8 and additionally showing componentsutilized to radiate the microwave beam from the fuselage of the aircraftoutwardly into the atmosphere both in front of the fuselage and alongthe leading edge of the wing.

FIG. 10 is a diagram of components of a second embodiment of theinvention showing microwave beams radiated through a wing portion of theaircraft and radiated outwardly into the atmosphere in front of theleading edge of the wing and into the rear of the trailing edge of thewing.

FIG. 11 is a diagram of the components of the second embodiment of theinvention shown in FIG. 10 and specifically showing in more detailcomponents utilized to radiate the microwave beam through the wingportion of the aircraft and radiated into the atmosphere in front of theleading edge of the wing.

FIG. 12 is a diagram of the components of the second embodiment of theinvention shown in FIG. 10 and specifically showing in more detailcomponents utilized to radiate the microwave beam through a wing portionof the aircraft and radiated into the atmosphere rearward of thetrailing edge of the wing.

FIG. 13 is a diagram of the components of the second embodiment of theinvention shown in FIGS. 10, 11 and 12 and specifically showing in moredetail components utilized to radiate the microwave beam from thefuselage of the aircraft outwardly into the atmosphere both in front ofthe fuselage and along the leading edge of the wing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Basically, the aerodynamic efficiency system of the invention utilizesthe microwave frequency selective absorption peaks of oxygen to provideeffective and efficient heating of portions of the atmosphere in thepath of a vehicle moving therethrough. Water and oxygen have electricand magnetic dipoles which enable them to more readily vibrate inresponse to microwave radiation. The microwave absorption peaks shown inFIG. 1 are the microwave frequencies at which harmonic resonanceexcitation of these types of molecules occur which maximizes heatproduced in response thereto. As shown in FIG. 1, maximum attenuation ofradiation occurs at the first oxygen peak of approximately sixty GHz andthis is therefore the frequency deemed optimum for energy efficientheating of the atmosphere. However, nitrogen molecules do not havesignificant dipole properties and therefore cannot efficiently be heatedby microwave radiation. Consequently, the nitrogen molecules in theatmosphere (as well as other types of molecules therein) are insteadindirectly heated by direct physical transfer of heat energy from oxygenmolecules which are proximal thereto thereby producing rapid heating ofan entire desired portion of the atmosphere. As is also evident fromFIG. 1, microwave radiation can also be used to heat a medium composedpartly or entirely of water thereby allowing a vehicle to move with lessfriction through a "tunnel" or "channel" of rarefied water in the pathof the vehicle.

Two preferred means of applying the concept of the present invention toa jet aircraft are described in a first embodiment and a secondembodiment generally designated by the numerals 10 and 110,respectively. FIGS. 2, 3 and 4 depict components of the invention commonto both embodiments and used in essentially the same way. FIG. 2 shows atypical jet engine 12 (112) which is suitable for use with the conceptof the present invention, and FIG. 3 depicts a microwave electromagneticradiation generator 14 (114) positioned in such an engine 12 (112)between the low pressure fan 28 (128) and the compressor turbine fansthereof 21 (121) for heat transfer between the induction and exhaustairflows 16 (116), 18 (118) and the generator 14 (114). The microwavegenerator 14 (114) is preferably a gyrotron tube 14 (114) although othersuitable types of microwave generators may also be utilized. Thegyrotron type 14 (114) is thus attached to the engine 12 (112) beforethe compressor 25 (125) and the compressor turbine fan 21 (121) andarranged so that it is in the path of the dense flow of air after thebypass fan 28 (128) of a low or high bypass jet engine 12 (112) butbefore the compressor of the engine 12 (112), as shown in FIG. 4 andwith reference to FIG. 2. The gyrotron tube 14 (114) is also preferablyoriented so that it is approximately transverse to the axis of the jetengine 12 (112), as shown in FIGS. 4, 6, 7, 10 and 11. The gyrotron tube14 (114) has an electron collector 22 (122) and collection of thegyrotron's 14 (114) electron beam generates heat which is the majorsource of heat due to the relative high density and high velocity of theelectron beam and super conducting magnets 23 (123) which must be keptcool to provide maximum power efficiency in maintaining magnetic fieldstrength. The electron collector 22 (122) is conventional in structureand function and is preferably cooled with water (although liquid sodiummay also be suitable) as with conventional gyrotron designs preferablyvia a conventional radiator subsystem suitably positioned in the path ofthe airflow 16 (116), while the super-conducting magnets are located atoutermost portions of the engine 12 (112) and wings 24 (124) of theaircraft 20 (120) thereby obtaining the required cooling directly fromthe atmosphere. The electron gun of the gyrotron 14 (114) forms anelectron beam which is accelerated through the focusing field of themagnets 23 (123) to the electron collector 22 (122). The electrons ofthe beam interact with radio-frequency electric fields perpendicular tothe magnetic focusing field. The rotation of the electrons in the fieldand the alternation of the fields in synchronism therewith produce acumulative interaction resulting in an oscillation. The interactionbetween the electrons and the fields causes the electrons to bunch in anelongate trajectories enabling extraction of energy from the electronsand by utilizing the resonance nature of the interaction producing thedesired high frequency output. As shown in FIG. 3, the coolant vanes 26(126) of the gyrotron tube 14 (114) are preferably mounted inside theengine 12 (112) for heat exchange with the induction airflow passingthrough the engine 12 (112). The vanes 26 (126) are preferably curved toconform with the laminar flow of the air generated by the bypass fans 28(128) of the engine 12 (121), but they are depicted as straight forsimplicity of illustration. The heat from the collector 22 (122) istransferred to the airflow 16 (116) passing into the low pressure fan 28(128) used to generate compressed cold air which is mixed with theengine's gas turbine hot exhaust 18 (118). The temperature of theexhaust airflow 18 (118) is thereby increased providing increased enginethrust while the electron collector 22 (122) is cooled withoutnecessitating the energy burden of a cooling subsystem specifically forcooling the collector. Thus, the efficiency of both the generator 14(114) and the engine 12 (112) are improved. This heat exchange could beused in a high bypass jet engine as well as a low bypass turbofan jetengine the latter of which would be more effective because a two orthree stage low pressure fan is used to generate compressed cold air (ahigh pressure compressor feeds the jet engine's fuel/air mixture).

The first embodiment 10 of the invention is shown generally in FIG. 5and more specifically in FIGS. 6, 7, 8 and 9. The first embodimentincludes the generators 14 and the components thereof which are mountedin the engines 12 of the aircraft 20, as described generally above. Thegenerators 14 preferably include a pair of continuous wave gyrotrons 15and 17 and a pulse gyrotron 19 mounted in each of the engines 12. Thepulse gyrotron 19 provides pulsed radiation which is emitted frompreferably the front portion of the fuselage 30 of the aircraft 20 inorder to allow radar and continuous wave (cw) communication subsystemsto be used in the aircraft. High speed interruption of the low frequencyaudio rates employed on a single channel VHF or UHF (cw) radiotransmitter is tolerable for such transmissions where the gyrotron 19operates with a pulse repetition interval of four-hundred microseconds(2500 pulses per second) and would also permit a thirty mile weather orengagement radar subsystem to operate effectively. The gyrotron 19preferably operates with a fifty percent duty factor, on forfour-hundred microseconds and off for four-hundred microseconds.

All of the gyrotrons 15, 17 and 19 utilize antennas to radiate themicrowave energy both directly outwardly of the aircraft 20 into theatmosphere and into and through inner structures of the aircraft 20 tolocations where the energy may be radiated directly into the atmosphere.Sets of preferably cassagrain types of output antennas 32, 76 and 78 aremounted at the output of each of the gyrotrons 15, 17 and 19 to emit theradiation into and through conduits which are preferably nitrogen filledwaveguides 34 (or simply nitrogen filled passageways) located within thewing 24 of the aircraft 20, as shown in FIG. 7. However, other types ofmicrowave radiation waveguides or conductors may also be utilized ifdesired and as appropriate for the particular application. Preferably aninverse cassagrain type of antenna 36 is mounted at appropriate fuselageportions of the aircraft 20 for receiving the radiation transmittedthrough the waveguide 34 and emission of the radiation directly into theatmosphere. The waveguides 34 preferably include a first set ofwaveguides 38, a second set of waveguides 40 and a third set ofwaveguides 42. The first set of waveguides 36 are preferably mountedwithin the wing 24 and positioned at the output of the gyrotrons 15 (andantennas 32) in order to receive the radiation output therefrom andtransmit and direct it to a first set of (preferably contoured) radomes44 at leading edges 46 of the wing 24. The second set of waveguides 40are preferably also mounted within the wing 24 and positioned at theoutput of the gyrotrons 17 (and antennas 76) in order to receive theradiation output therefrom and transmit and direct it to a second set ofradomes 48 at trailing edges 50 of the wing 24. The third set ofwaveguides 42 are preferably mounted within the wing 24 and the fuselage52 and positioned at the output of the gyrotrons 19 (and antennas 78) inorder to receive the radiation output therefrom and transmit and directit to a third set of radomes 54 at the front portion (or tip) 30 of thefuselage 58. The sets of radomes 44, 48 and 54 are preferably composedof sintered aluminum oxide to provide heat and oxidation resistancewhile also allowing the microwave radiation to pass therethrough intothe atmosphere. The sets of radomes 44, 48 and 54 are also positioned atsurface portions of the aircraft 20 in the path of the microwaveradiation beams exiting the aircraft 20 and emitted into the atmosphere.

A first set of mirrors 56 are also included and positioned at preferablythe distal end of the first set of waveguides 38 for receiving theradiation beam transmitted through the set of waveguides 38 andreflecting the beam generally backward into and through the first set ofradomes 44 and outward into the atmosphere in front of the wing's 24leading edge 46. The reflected beam is preferably angled relative to theleading edge 46 so that it is nearly parallel thereto and morepreferably at an angle of approximately fifteen degrees relativethereto, as shown in FIGS. 6 and 7. Thus, the beam is oriented such thatalthough it is projected so that it is directly in front of the entirelength of leading edge 46 it is not positioned at an excessive distancefrom any portion of the leading edge 46 and therefore does not heat aportion of the atmosphere an excessive distance from the leading edge46.

The output of the continuous wave gyrotron 15 is fed into the first setof cassagrain output antennas 32 which are oriented so that they emitthe radiation directly into the first set of waveguides 38 as well asinto and through the first set of radomes 44, as shown in FIG. 7. Thus,a portion of the beam emitted from the output antenna 32 is transmittedinto the first set of waveguides 38 while another portion of the beamemitted therefrom is transmitted into the first set of radomes. Theportion of the radiation beam transmitted through the first set ofradomes 44 directly from the output antenna 32 is emitted into theatmosphere directly in front of the leading edge 46 and approximatelyparallel thereto. The beams reflected into the atmosphere in front ofthe leading edge 46 from the mirrors 56 and directly from the outputantenna 32 are directed generally towards each other.

The output of the continuous wave gyrotron 17 is fed into another set ofcassagrain output antennas 76 which radiate the microwave beam into andthrough the second set of waveguides 40. A second set of mirrors 58positioned in the second set of waveguides 40 reflects and directs thebeam into and through the second set of radomes 48 into the atmospheredirectly rearward of the trailing edges 50. More specifically, theradiation beam is radiated through the second set of waveguides 40 ontoa second set of mirrors 58, located at approximately midwing, whichdirect the beam rearwardly. The second set of radomes 48 at the trailingedges are wider than the first set of radomes 44 at the leading edge andconsequently a larger region of aft wing heats the air leaving thewing's surface.

A portion of the microwave beam transmitted through the second set ofwaveguides 40 is directed onto a third set of mirrors 60 located in thefuselage 52 which reflect the beam toward a fourth set of radomes 62located at the vertical leading edge 64 of the tail stabilizer 66. Morespecifically, a third set of mirrors 60 located at a bend in thewaveguide (preferably in the fuselage 52) reflects the beam rearwardlythrough the waveguide 40 and the fuselage 52 to another of the third setof mirrors 60 located proximal the tail stabilizer 66 which reflects thebeam into and through the fourth set of radomes 62 and outwardly intothe atmosphere directly in front of the tail stabilizer 66 leading edge64. The beam emitted into the atmosphere from the fourth set of radomes62 is oriented so that it is generally parallel to the tail stabilizer's66 leading edge 64, as is the beam emitted from the antenna 32 directlyinto the atmosphere in front of the leading edge 46 of the wing 24, asdescribed above.

The output of the pulse gyrotron 19 is fed to the third set of thecassagrain antennas 78 which radiate it into and through the third setof waveguides 42 and through the third set of radomes 54 into theatmosphere directly in front of the front portion 30 of the fuselage 52.As shown in FIGS. 6 and 9, a fourth set of mirrors 68 located in thefuselage and at a bend in the third set of waveguides 42 reflects thebeam forwardly through the fuselage 52 into one of the inversecassagrain antennas 36 which emits the radiation beam into and throughthe third set of radomes 54. As with the other of the inverse cassagrainantennas 36, this inverse cassagrain antenna 36 emits a broadened beamof radiation into the atmosphere directly in front of the front portion30 of the fuselage 52. In addition, there is also a seventh mirror orset of mirrors 70 mounted in the fuselage 52 which receives, reflectsand directs a portion of the pulsed radiation beam transmitted throughthe fuselage 52 into and through the first set of radomes 44 andoutwardly into the atmosphere directly in front of the leading edge 46.As described above, the radiation emitted from the fuselage 52 is pulsedin order to allow both radar and continuous wave communications signalsto be transmitted and received while the aerodynamic efficiencyaugmentation system of the present invention is in operation.

In addition, some of the remaining microwave radiation is fed directlyfrom the output antenna 32 to the electromagnetically conducting skin 74of the wing 24 by means of an electric conductor (or waveguide) 72, asshown in FIG. 7. The microwave radiation is thus allowed to betransmitted directly through the outer surface 74 of the wing (and otherparts of the aircraft 20 such as the fuselage 52, if desired). Thisradiation being conducted through the outer surfaces 74 heats the airadjacent thereto resulting in reduced viscous drag for these portions ofthe aircraft 20.

FIGS. 10, 11, 12 and 13 show the second embodiment of the invention 110which is essentially identical to the first embodiment 10 except thatthe microwave beams are radiated outwardly in front of the leading edges146 in a direction generally parallel to the direction of motion of theaircraft 120 rather than at a small angle (or nearly parallel) to theleading edge 46 i.e., approximately perpendicular to the direction ofmotion, as in the design of embodiment 10. The rays of the radiationbeam emitted from the leading edges 146 are also divergent from eachother, as shown in FIG. 11. In the embodiment 110, a fifth set ofmirrors 155 is provided which receive the radiation beam emitted fromthe first set of cassagrain output antennas 132. The fifth set ofmirrors 155 are located in the first set of waveguides 138 at locationsalong the length thereof behind the leading edges 146 of the wings 124,as shown in FIG. 10. The fifth set of mirrors 155 are oriented so thatthey reflect and direct the radiation beam into and through a first setof radomes 144 mounted at the surface portions of the leading edges 146and into the atmosphere directly in front of the leading edges 146. Theremainder of the radiation beam transmitted through the first set ofwaveguides 138 which is not emitted through the first set of radomes 144via reflection from the fifth set of mirrors 155 is reflected off afirst and sixth set of mirrors 156 and 157 located at the inner endportion of the first set of waveguides 138 at or proximal to thefuselage 152 and directed to the first set of radomes 144 at the leadingedge 146 of the wing for emission into the atmosphere in front of theleading edge 146. The radiation beam emitted from the first set ofmirrors 156 through the first set of radomes 144 is oriented such thatit is preferably angled relative to the leading edge 146 so that it isnearly parallel thereto and more preferably at an angle of approximatelyfifteen degrees relative thereto, as shown in FIG. 10 and similar to theangle produced by the first set of mirrors 56 of embodiment 10. Thesixth set of mirrors 157 is oriented so that it is more nearlyperpendicular to the direction of transmission of the radiation beamthrough the first set of waveguides 138 and thus reflects and directsthe radiation beam through the first set of radomes 144 in a directionlaterally outward from the aircraft 120 and in front of the leading edge146. The sixth set of mirrors 157 is oriented so that the angle of theradiation beam reflected therefrom is more obtuse than that of the beamreflected from the first set of mirrors 156 and this angle is preferablyapproximately 30 degrees. Thus, each of the beams is oriented such thatalthough it is projected so that it is directly in front of the entirelength of leading edge 146 it is not positioned at an excessive distancefrom any portion of the leading edge 146 and therefore does not heat aportion of the atmosphere an excessive distance from the leading edge146.

As shown in detail in FIG. 12, the output of the continuous wavegyrotron 117 is fed into a second set of cassagrain output antennas 176which radiate the microwave beam into and through the second set ofwaveguides 140. A second set of mirrors 158 positioned in the second setof waveguides 140 reflects and directs the beam into and through thesecond set of radomes 148 into the atmosphere directly rearward of thetrailing edges 150. The emission of the radiation beam from the trailingedges 150 is accomplished using structures which are identical to andfunction the same as correspondingly numbered components described abovewith respect to embodiment 10. The radiation beam is radiated throughthe second set of waveguides 140 onto a second set of mirrors 158,located at approximately midwing, which direct the beam rearwardly intoan inverse cassagrain antenna 136 which emits the radiation beam intoand through the second set of radomes 148 outwardly and rearwardly intothe atmosphere rearward of the trailing edges 150. As with thecorresponding structures of embodiment 10, the second set of radomes 148at the trailing edges 150 are wider than the first set of radomes 144 atthe leading edge and consequently a larger region of aft wing heats theair leaving the wing's surface.

A portion of the microwave beam transmitted through the second set ofwaveguides 140 is directed onto a third set of mirrors 160 located inthe fuselage 152 which reflect the beam toward a fourth set of radomes162 located at the vertical leading edge 164 of the tail stabilizer 166.As with the correspondingly numbered components of embodiment 10, thethird set of mirrors 160 reflects the beam rearwardly through thewaveguide 140 and the fuselage 152 to another of the third set ofmirrors 160 located proximal the tail stabilizer 166 which reflects thebeam into and through the fourth set of radomes 162 and outwardly intothe atmosphere directly in front of the tail stabilizer 166 leading edge164 and generally parallel to the leading edge 164.

The output of the pulse gyrotron 119 is fed to a third set of thecassagrain antennas 178 which radiate it into and through the third setof waveguides 142 and through the third set of radomes 154 into theatmosphere directly in front of the front portion 130 of the fuselage152. The components utilized to accomplish this emission of radiationfrom the front portion 130 of the fuselage are structurally andfunctionally identical to the correspondingly numbered components ofembodiment 10. As shown in FIGS. 5 and 13, a fourth set of mirrors 168located in the fuselage and at a bend in the third set of waveguides 142reflects the beam forwardly through the fuselage 152 into one of theinverse cassagrain antennas 136 which emits a preferably pulsedbroadened beam of radiation into and through the third set of radomes154. There is also a seventh mirror or set of mirrors 170 mounted in thefuselage 152 which receives, reflects and directs a portion of thepulsed radiation beam transmitted through the fuselage 152 into andthrough the first set of radomes 144 and outwardly into the atmospheredirectly in front of the wing's 124 leading edge 146.

The cassagrain antennas 32, 132, 76, 176, 78 and 178 include acassagrain primary aperture which is approximately thirteen centimetersin diameter in order to provide a radiation beam the rays of which aredivergent at an angle of approximately 2.5 degrees. This beam istransmitted through the appropriate sets of waveguides 38, 40 and 42where it gradually expands as it passes therethrough. The inversecassagrain antennas 36 and 136 include a cassagrain primary aperturewhich collects the radiation transmitted through the appropriatewaveguide and reflects it through a smaller aperture. This effectivelybroadens the beam so that the rays thereof diverge from each other at anangle of approximately nineteen degrees in order to heat a region of airtwo meters wide six meters in front of the aircraft. As set forth in thecalculations, the primary aperture is approximately in excess ofthirteen centimeters in diameter while the secondary aperture isapproximately 1.7 centimeters in diameter. However, the particularsizing of these components depends on the physical design of theaircraft, its flight envelope, etc. and will thus vary in accordancewith the particular application.

Accordingly, there has been provided, in accordance with the invention,a system for increasing the aerodynamic efficiency of a vehicle inmotion that fully satisfies the objectives set forth above. Although theinvention has been described in regard to increasing the aerodynamicefficiency of an aircraft in flight, the system of the invention mayalso be applied to other types of vehicles or bodies in motion throughother types of fluid media. It is to be understood that all terms usedherein are descriptive rather than limiting. Although the invention hasbeen described in conjunction with the specific embodiments set forthabove, many alternative embodiments, modifications and variations willbe apparent to those skilled in the art in light of the disclosure setforth herein. Accordingly, it is intended to include all suchalternatives, embodiments, modifications and variations that fall withinthe spirit and scope of the invention set forth in the claimshereinbelow.

What is claimed is:
 1. A system for increasing the dynamic efficiency ofa vehicle in a fluid medium, comprising:a source of electromagneticradiation; means for transmitting electromagnetic radiation from saidsource to desired surface portions of the vehicle, said surface portionsincluding leading edges, said means for transmitting receiving theradiation from said source; means for emitting a beam of the radiationoutwardly and away from the desired surface portions, the leading edgesand the vehicle in order to heat the fluid medium thereby reducing massdensity of the fluid medium to reduce dynamic drag on the vehicle, saidmeans for emitting receiving the radiation from said means fortransmitting, said desired surface portions adjacent to areas of thefluid medium heated by the radiation.
 2. The system of claim 1 whereinfrequency of the radiation is approximately a harmonic resonancefrequency of electromagnetic excitation of molecules of the fluid tomaximize heating thereof, the molecules of the fluid having electric andmagnetic dipole characteristics so that the molecules are excitable bythe electromagnetic radiation at the harmonic resonance frequency. 3.The system of claim 1 wherein said means for transmitting includes a setof waveguides interconnecting said source and the desired surfaceportions.
 4. The system of claim 3 wherein said means for emittingincludes an inverse cassagrain antenna having an aperture for receivingradiation transmitted through said set of waveguides and emitting theradiation through the surface portions and into the fluid medium theradiation at a microwave frequency.
 5. The system of claim 3 whereinsaid means for transmitting includes an output cassagranian antenna fordirecting a first portion of the radiation from said source into saidwaveguide and a second portion of the radiation from said source into aportion of the fluid medium proximal to the vehicle.
 6. The system ofclaim 5 wherein said antenna is connected to an outer surface of thevehicle for transmission of the radiation through the outer surface inorder to heat an area of the fluid medium adjacent thereto.
 7. Thesystem of claim 1 wherein said means for transmitting includes a mirrorfor deflecting and directing the beam to the desired surface portionswith minimal scattering thereof.
 8. The system of claim 1 wherein saidmeans for transmitting, said means for emitting and said source aremounted within the vehicle.
 9. The system of claim 1 wherein said sourcehas sufficient power to provide the radiation at an energy densitysufficient to heat the fluid medium to a temperature of approximately1800 degrees Centigrade.
 10. A system for increasing the dynamicefficiency of a vehicle moving in a fluid medium, comprising:a source ofmillimeter wavelength electromagnetic radiation at a selected frequencyhigher than fifty Gigahertz; means for transmitting millimeterwavelength electromagnetic radiation at the selected frequency from saidsource to desired surface portions of the vehicle, said means fortransmitting receiving the radiation from said source; means foremitting a beam of the radiation outwardly and away from the desiredsurface portions in order to heat the fluid medium thereby reducing massdensity of the fluid medium to reduce dynamic drag on the vehicle, saidmeans for emitting receiving the radiation from said means fortransmitting, the fluid medium including molecules having electric andmagnetic dipole characteristics excitable by the millimeter wavelengthelectromagnetic radiation which is tuned to a frequency of harmonicresonance electromagnetic excitation of the molecules.
 11. The system ofclaim 10 wherein said means for transmitting includes a waveguideinterconnecting said source and at least one of the desired surfaceportions.
 12. The system of claim 10 wherein said means for emittingincludes an inverse cassagrain antenna for receiving radiationtransmitted through said portions and into the fluid medium, saidcassagrain antenna including a primary reflector having an aperture anda secondary reflector small relative to the primary reflector, saidprimary and secondary reflectors positioned so that the radiation isradiated through the aperture and reflected off the secondary reflectorback into said primary reflector where it is reradiated into the fluidmedium in a narrow beam the rays of which are divergent at an angle ofapproximately nineteen degrees.
 13. The system of claim 10 wherein saidmeans for transmitting includes a waveguide for propagating theradiation and a mirror mounted in said waveguide for deflecting anddirecting the beam to at least one of the desired surface portionswithout scattering thereof.
 14. The system of claim 10 wherein saidmeans for transmitting, said means for emitting and said source aremounted within the vehicle.
 15. The system of claim 10 wherein saidsource has sufficient power to provide the radiation at a power densitysufficient to continually heat the fluid to a temperature ofapproximately 1800 degrees Centigrade.
 16. A system for increasing thedynamic efficiency of a vehicle moving in a fluid medium, comprising:asource of electromagnetic radiation; means for transmittingelectromagnetic radiation from said source to desired surface portionsof the vehicle, said means for transmitting receiving the radiation fromsaid source; means for emitting a beam of the radiation outwardly andaway from the desired surface portions and away from the vehicle intothe fluid medium so that the fluid medium absorbs substantially all theelectromagnetic radiation energy thereof in order to heat the fluidmedium thereby reducing mass density of the fluid medium to reducedynamic drag on the vehicle, said means for emitting receiving theradiation from said means for transmitting, said surface portionsadjacent to areas of the fluid medium heated by the radiation.
 17. Asystem for increasing the dynamic efficiency of a vehicle moving in afluid medium, comprising:a source of electromagnetic radiation at afrequency of approximately sixty Gigahertz; means for transmittingelectromagnetic radiation at the frequency of sixty Gigahertz from saidsource to desired surface portions of the vehicle, said means fortransmitting receiving the radiation from said source; means foremitting a beam of the radiation outwardly from the desired surfaceportions into the fluid medium in order to heat the fluid medium therebyreducing mass density of the fluid medium to reduce dynamic drag on thevehicle, said means for emitting receiving the radiation from said meansfor transmitting.
 18. A system for increasing the dynamic efficiency ofa vehicle moving in a fluid medium, comprising:a source ofelectromagnetic radiation, said source of electromagnetic radiationincluding a pulsed gyrotron to allow radar to be used on the vehicle anda continuous wave gyrotron, said pulsed and continuous wave gyrotronslocated at an engine of the vehicle and positioned in a path of engineinduction flow for heat exchange between engine induction and exhaustflow and said gyrotron in order to enhance energy efficiency thereof;means for transmitting electromagnetic radiation from said source todesired surface portions of the vehicle, said means for transmittingreceiving the radiation from said source; means for emitting a beam ofthe radiation outwardly and away from the desired surface portions intothe fluid medium in order to heat the fluid medium thereby reducing massdensity of the fluid medium to reduce dynamic drag on the vehicle, saidmeans for emitting receiving the radiation directly from said means fortransmitting or directly from said source of electromagnetic radiation.19. A system for increasing the dynamic efficiency of a vehicle movingin a air medium, comprising:a source of electromagnetic radiation; meansfor transmitting electromagnetic radiation from said source to desiredsurface portions of the vehicle, said means for transmitting receivingthe radiation from said source; means for emitting a beam of theradiation outwardly and away from the desired surface portions into thefluid medium in order to heat the air medium thereby reducing massdensity of the air medium to reduce dynamic drag on the vehicle, saidmeans for emitting receiving the radiation from said means fortransmitting, the air medium including molecules having electric andmagnetic dipole characteristics excitable by the electromagneticradiation which is tuned to a frequency of harmonic resonanceelectromagnetic excitation of the molecules.